Field of the Invention
The present technical field relates to a method for producing a semiconductor light-emitting device exhibiting improved light extraction efficiency.
Background Art
Brightness of the semiconductor light-emitting device depends on the internal quantum efficiency and the light extraction efficiency of the device. Therefore, the techniques have been developed to improve the internal quantum efficiency and the light extraction efficiency of the device. The techniques to form an uneven light extraction surface have been developed to improve the light extraction efficiency.
Japanese Translation of PCT International Application Publication No. 2015-509663 discloses a light-emitting device having a plurality of protrusions 25a on a surface of an n-type semiconductor layer 25 and small cones 25b formed on the top surfaces of the protrusions 25a (refer to paragraph [0037] and FIG. 2). Disclosed is the techniques to form the small cones 25b formed on the top surfaces of the protrusions 25a by wet etching after the protrusions 25a were formed by dry etching (paragraphs [0062] to [0066] and FIGS. 9 to 11).
The semiconductor light-emitting device has a flip chip to extract light from the substrate. In the flip-chip type light-emitting device, an uneven shape may be formed on the light extraction surface formed on the substrate. For example, when forming the uneven shape by etching, a flat surface may be generated between the protrusions. The flat surface between the protrusions reflects light. Therefore, fine protrusions and recesses are preferably formed on the flat surface between the protrusions.